Forklift trucks are well-known devices for moving and stacking large quantities of light or heavy materials. Forklift trucks may be of the counterbalanced or straddle-leg design and usually are large enough to carry a driver and move about in all types of warehouse and manufacturing areas. For a few specialized purposes forklift trucks have been miniaturized and carried on a highway transport truck by hanging from the rear of the truck or carried inside the cargo space of a rear-loading truck. In U.S. Pat. No. 3,799,379 and U.S. 4,180,363, there are shown forklift trucks that can attach their lifting forks to stirrups on the bed of a transport truck, lift themselves off the ground up to the truck bed, and be secured in that position for highway transport to any location. In U.S. Pat. No. 4,061,237, there is shown a collapsible forklift truck that can lift itself into a transport truck and be stored in a folded state inside the truck. While these forklift trucks are usable for many purposes, they are not appropriate for tasks such as unloading entire or partial pallet loads from a side-loading freight truck, such as a beverage truck, and moving those unit loads of freight on pallets through narrow doors, hallways, and crowded aisles to the inside of congested stores. Previously, this task was accomplished with much manual labor and usually no powered self-propelled equipment. Forklift trucks have not been made of such a size, weight, and configuration that they can carry a full pallet load readily through an ordinary door slightly larger than a pallet load in width, while being able to set the pallet down on the floor between the straddled front wheels, and yet, when stored out of use, be made sufficiently compact to be carried within the area of a single pallet in one bay of a side-loading highway truck. Delivery of cases of beverage from a truck parked outside a delivery building to inside storage areas or directly to sales areas involves special problems that could be greatly alleviated by the assistance of any self-propelled equipment with the before-mentioned characteristics.
It is an object of this invention to provide a small, collapsible forklift truck that is self-propelled, can be transported in a collapsed condition along with the highway truck, and in a few moments can be made available to unload and transport freight from the truck into a building, or transport freight from the building and load it into the highway truck. It is another object of the invention to provide a forklift truck which is self-propelled and which can, while moving with or without a transported load, spread its front wheels apart in preparation for setting a load on the floor or close the front wheels inward under the load area when it is necessary to pass through a narrow opening, such as a door, hall way, or aisle which is only slightly wider than the width of the unitized load being transported. Still other objects will appear from a more detailed description of this invention which follows.